About ACT 4 Puck Sprung Clutch Disc:
An ACT 4-Puck Sprung Hub Race Disc has very harsh engagement and is designed for road race cars only. A G4 friction surface has good durability and spline life characteristics under normal use. The sprung hub helps to reduce driveline shock and be relatively quiet compared to an unsprung hub but will definitely have chatter. The ACT G4 is SFI certified, so it is legal for all forms of racing that require SFI compliance. Not recommended for a daily driven/street car.